Door for top loading and unloading ovens



July 6 1943- c. F. MAYER 2,323,828

DOOR FOR TOP LOADING AND UNLOADINO OVENS Filed Aug. 1, 1942 5 Sheets-Shea?I l m ,f7 lu" 5| Inl al IN V EN TOR.

July 6, 1943. Q F, MAYER v 2,323,828

DOOR FOR TOP LOADING AND UNLOADING OVENS E iled Aug. l, 1942 3 Sheets-Sheet 2 HG. INVENTOR. I BY QDQNQ Mmm A my July s, 1943. c. F. MAYER' 2,323,828

DOOR FOR TOP LOADING AND UNLOADING OVENS Filed Aug. l, 1942 3 Sheets-Sheet 5 INVENTOR.

4m QAM y Patented July 6, 1943y UNITED STATES PATENT OFFICE Doon Fon 'roP LoADmG AND UNLoAnlNG ovENs r Carl F. Mayer, Lakewood, Ohio Application August 1, 1942, Serial No. 453,272

19 Claims.

The present invention consists of improvements in doors or shutters for top loading and unloading ovens of the kind that constitutes the subject matter of my copending appplication Serial No. 273,719, filed May 15, 1939, now Patent No, 2,296,361. l

lOvens of the sort mentioned are peculiarly suited to rod or wire baking and accordingly are customarily termed rod bakers, and in the use thereof several coils of rod or wire are supported on a bar or so-called pin and are lowered into and removed from the oven in a vertical direction. 'I'he doors or shutters of my invention, herein disclosed as those of a rod baker, are biased toward and normally repose in a horizontal or closed position and yield in both upvrard and downward directions to the passage requirements of different jobs; and which doors l or shutters, with their associated mechanisms,

are relatively simple oi construction, reliable of action and very durable. y

An embodiment of the invention through which f 'he foregoing objects, with others hereinafter ppearing, are attained is illustrated in the accompanying drawings wherein like reference characters designate corresponding parts throughout the several views.

In the drawings, Fig. 1 is a plan view of a top loading and unloading oven equipped with vthe doors or shutters of my invention; Fig. 2,v

represents a vertical transverse section through the oven substantially on the line 2 2 of Fig. 1; Fig. 3 is a fragmentary end elevation of the oven; Fig. 4 is a sectional view taken on the line 4-4 of Fig. 3; Fig. 5 is a sectional detail on the line 5 5 of Fig. 3; Fig. 6 is a sectional detail on the line 6-6 of Fig. 4; Figs. 7 and 8 are diagrammatic views showing certain parts associated with one of the -doors in the position they occupy when the door is depressed, and when the door is raised, respectively; Fig. 9 is a perspective view of one of the yielding stops for the arms on the door shafts, said view being taken from .below the plane of the stop; Fig. 10 Sheet 1) is a fragmentary perspective view of one of the shafts, showingthe key secured thereto, and Fig. 11 is a similar view of one of the arms showing the portion of the hubwherewlth said key cooperates.

The oven is designated, generally, by the refence numeral I, and it consists of a rectangular casing that is made up of insulated bottom,y side Y andend'walls, according to usual practice. A

cover 5, desirably fabricated of metal plates, 'partially closes the top of the oven, the same extending along the two sides 'and across the ends, the

end portions of said cover, at about their middle,

being provided with notches 1 through which the ends of a beam are adapted to pass when theload is lowered into and removed from the oven,

Below as will hereinafter more fully appear. each notch 1 is a seat 8 for supporting the adjacent end of the before-mentioned beam.

Referring now to Fig. 2: .Duets I0 and II, and manifolds I2, all provided with suitable openings, are arranged within the oven, and .by a

system of conduits and fluid impellers (not shown) that are common in connection with such ovens, heated air or gas is circulated through the oven, the same being projected into the oven through the openings of the manifolds I2 and',

desirably, through the openings of the ducts I0, and drawn 01T adjacent the top of the oven through the openings of the ducts I I.

Channel bars I4 are disposed in parallel relation to each other longitudinally of the oven top, and they are shown as mounted upon, and as located ,adjacent the inner edges of, the side portions of the cover 5. An elongated element or shaft I5 extends along the inner side of,A each of said channel bars, near the base thereof, and said shaft isshown as rotatably lconnected to .said

bar by hangers or knuckles I6. At the endsfof the oven, the shafts I5 are journaled inl substantial bearings I1; and the shafts project an' ap-` preciable distance beyond the bearings at one end of the oven, and adjacent to said bearings have shaft I5, desirably by welding, within the spaces` between the end portions of the cover 5 are doors or shutters 20, whose free edges are spaced apart, when the doors or shutters are in normal or closed position, a distance approximately equal to the maximum width of the notches 1.

Each door 20 consists of a metal plate that is turned downwardly and inwardly along the free edge of the door, as shown at 2I, about a core 22 (Fig. 3) that may consist of a piece of standard pipe of proper length, the inturned edge of the plate being welded to the underneath side of the body portion of theplate. Each door is shownas provided with a depending end ange 25 of a width approximately equal to the diameter of the core 22. Strengthening ribs 24, shown in the form of angle irons, are welded or other-V wise secured to, and are arranged transversely of, the doors and their ends adjacent the shafts I are suitably fastened thereto, as by welding.

As will beseen from the foregoing description, the cover 5 and the doors 20 close the top of the oven except for a comparatively narrow opening that extends centrally and longitudinally of the oven between the doors and is made up in part of the notches 1. While this opening permits a limited amount of fumes to escape from the oven, the result is relatively'unobjectionable in plants of the kind wherein such ovens are employed. If desired, however, said space may be closed by a suitable bonnet, such as that indicated in dot-and-dash lines in Fig. 2, where it is designated and the same may be carried by the beam or rigging from which is suspended the bar or pin that supports the coils of rod or wire. Since the bonnet. according to the present proposed embodiment, is carried by said beam or rigging, it is absent from the aforesaid opening during the intervals .between baking or drying operations, but this is of no consequence when the practice is followed of shutting oil' the fluid impelling means that circulates the hot air or gases through the oven, during said intervals.

Journaled on the end of each shaft I5 beyond the key I8, for free but limited rotary motion relative to the shaft, is the hub 29 of a member or arm 30. The inner end of said hub is cut away to provide a notch 3 I' (Fig. 11) for the accommodation of the key I8 and the circumferential extent of said notch is sulciently in excess of that of the key to provide relative movement between the arm and shaft through an angle of a. little less than 90. According to the present embodiment, the end walls of the notch in the hub 29 of each arm are approximately 180 apart, while the radial faces of the key that cooperate with said end walls are slightly over 90 apart. 'I'he reason for so proportioning the parts will presently appear. The arms 30 are held on the shaft by collars 34 which are suitably attached to the shafts.

Fastened to the free end of each arm 30, as will best appear from Figs. 3, 7 and 8, is a flexible element 4I), desirably consisting of a wire rope, that is guided over a sheave 4I and is operatively connected a suitable distance therebeyond, to counterbalancing means, herein shown as a weight 42. The effectiveness of said counterbalancing means is desirably capable of being altered or varied, and this end is attained in the present instance by making the weight 42 in sections and removably mounting said sections upon a support or stem 44 (Fig. 3) to which the exible element is attached. By reason of this construction, the total weight may be changed by increasing or decreasing the number of sections used. The sheave 4I' is rotatably supported on a stud 45 that projects laterally from a bracket 46 carried by the oven structure.

Associated with each of the arms 30 is a yielding stop designated generally by the .reference numeral into engagement with which the am is swung by the action of the counterbalancing means or weight 42. As best shown in Figs. 3. 5 and 9, each stop 50 consists of two U-shaped members 5I that are rigidly held in spaced paralle] relation to each other by a base portion 52 shown as a relatively short angle bar, the said members being secured to the bar preferably by welding. Guided at its ends within the bifurcations of the U-shaped members 5I is a striker plate 53 having guiding notches 54 for the reception of the branches of the U-shaped members. Welded or otherwise secured to the inner face of the striker plate, midway between the members 5I, is a stud 55 that is threaded at its end remote from the striker plate and is projected freely through a hole in one flange of the base 52 beyond which stop nuts 56 are applied to the stud. A relatively strong coil spring 55 surrounds the stud 55 and is compressed between the striker plate 53 and the base 52, the spring normally retaining the striker plate with its outer face slightly beyond the ends of the members 5I. The base 52 includes an extension 59, at present provided by a small angle piece that is welded to the base 52, and through the enlarged bearing surface thus effected, the base is engaged with a structural part of the oven I and is secured thereto by fastening means 60, such as bolts or rivets.

Referring again to Fig. 2: B is the beam from which is suspended, through hangers H, the bar or pin P that supports the coils C of wire or rod that is to be treated, these parts being shown in dot-and-dash lines.

In describing the operation of the invention it will be assumed that a load is present in the oven, under which circumstances the ends of the beam B rest within the seats 8. After the rod or wire has been left in theV oven long enough to bake or dry the lime or other coating thereon, the beam B is elevated to withdraw the load from the oven. As the coils C rise they engage the reinforced free edges of the doors 20 and lift the doors sufiiciently to permit the coils to pass between them, the distance to which the doors are raised being determined by the maximum diameter'of the coils, as will be readily understood.

As the doors are lifted they rotate the shafts I5 and swing the keys I8 idly within the notches 3| of the hubs of the arms 30, leaving the arms resting against the stops 50 under the influence of the counterbalancing means or weights 42. When the load has ascended sufllciently to withdraw from and thus release the doors. the doors drop of their own weight, reversing the former direction of rotation of the shafts I5 and swinging the keys I 8 against the upper end walls of the notches 3| in the hubs of the arms 30. The shock resulting from this action is absorbed somewhat by the counterbalancing means or weights 42, it being explained that the counterbalancing means or weight is so adjusted that the power thereof is only slightly more than that necessary to retain the doors 20 in horizontal o closed position. A As hereinbefore pointed out. the relative circumferential dimensions of the keys I8 and notches 3| in the hubs of the arms `35 are such as will permit slightly less than of angular movement between the shafts and arms. As a consequence, the doors are prevented from swinging upwardly to or beyond a vertical position, where they might be left on dead center, so to speak, or overbalanced outwardly beyond a. vertical position, under which circumstances they would fail to close automatically.

When a load is lowered into the oven, the coils C engage and depress the doors suillciently to permit the passage of the load, and duringthis action the keys I8, engaging the upper end walls of the notches 3i of the arms 30, cause said arms to swing upwardly to somewhat the position shown in Fig. 7. When the load descends far enough to release the doors, the counterbalancing means or weights I2 return the parts to normal position, the arms 30 striking the yielding stops 5B, the springs 58 whereof serve as shock absorbers and reduce the Jar resulting from the impact of the arms against the striker plates 53. vHere the advantage is again apparent of maintaining the power of the counterbalancing means or weight only slightly greater than that necessary to retain thedoors 20 in horizontal position, as otherwise the impact would be unnecessarily severe.

Having thus described my invention, what I claim is:

l. In a top loading and unloading oven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, s'aid elements being disposed longitudinally of the oven and spaced apart la-terally thereof a substantial distance, doors carried by said elements and extending therefrom toward each other and capable of swinging in unison with said elements said elements above and below, a substantially l horizontal position, and counterbalancing means above and below a substantially horizontal posil of alterable power tending to retain the elements in the position they occupy when the doors are in substantially horizontal position, the elements being movable independently of said biasing means when the doors are swung above horizontal position.

5. In a top loading and unloading oven, two tlements supported Afor oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, said elements being disposed longitudinally of the oven and spaced apart laterally thereof a substantial distance, doors rigidly connected to said elements and extending therefrom toward each 'other, and counterbalancing means tending to retain the elements in the position they occupy when the doors are substantially horizontal.

6. In a top loading and unloading oven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, said elements being disposed longitudinally of the oven and spaced apart laterally thereofA a substantial distance, doors connected to said ele- `inents and extending therefrom toward each other, and adjustable weights operatively connected to said elements and tending to retain them in the position they occupy when the doors are substantially horizontal. y

7. In a, top loading and unloading oven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially .parallel relation to each other, said elements being disposed longitudinally of the oven and spaced apart laterally thereof a substantial distance, doors carried by said elements and extending therefrom toward each other, and an oscillatory member operatively connected to each of the aforesaid elements,

horizontal position, arid means biasing the elements to the position they occupy when the doors are in substantially horizontal position, the ele-` ments being movable independently of said biasing means when the doors are swung above horizontal position.

3. In a top` loading and unloading oven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, said elements being disposed longitudinally of the oven and spaced -apart laterally thereof a substantial distance, doors carried by said elements in substantially parallel relation to each other,

said elements being disposed longitudinally of the oven and spaced apart laterally thereof a vsubstantial dis-tance, doors carried by said elements and extending therefrom toward each other and capable of swinging in unison vwith each element, by reason of the nature of the connection between itand the corresponding member moving in unison with said member when the door that is carried by said element is swung downwardly from a substantially horizontal position and independently of said member when the door is swung above said position, vand means biasing the member to the position it occupies when the door is substantially horizontal. s

8. In a top loading and unloadingoven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, saidelements being disposed longitudinally of the oven and spa-ced apart laterally thereof a .substantial distance, doors carried by said eletially horizontal position, and further means l tending to urge the members into cooperationY with the stop means.

9. In a top loading and unloading oven, in combination with the oven structure, two shafts arranged adjacent the top plane of said structure in substantially parallel relation to each other, said shafts being disposed longitudinally Voi the oven structure and spaced apart laterally thereof a substantial distance, bearings adjacent the ends of the oven structure wherein said shafts are supported for oscillation, two arms, one journaled on each shaft beyond one end of the oven structure, stop means wherewith each arm engages for limiting its movement in one direction, means biasing the arms in a direction to engage said stop means, doors connected to said shafts and extending toward each other in a substantially horizontal position when the shafts bear a given angular relation to the aforesaid arms, and lost motion connections between the shafts and arms which permit the shafts to rotate independently of the arms when the doors are swung above said horizontal position, said connections being such that the shafts and arms move in unison when the doors are swung below horizontal position.

10. In a top loading and unloading oven, in combination with the oven structure, two shafts arranged adjacent the top plane of said structure in substantially parallel relation to each other, said shafts being disposed longitudinally of the oven structure and spaced apart laterally thereof a substantial distance, bearings adjacent the ends of the oven structure wherein `said shafts are supported for oscillation, two arms, one journaled on each shaft beyond one end of the oven structure, stop means wherewith each arm engages for limiting its movement in one direction, an adjustable weight operatively connected to each arm and tending to swing it in a direction to engage said stop means, doors connected to said shafts and extending toward each other in a` substantially horizontal position when the shafts bear a given angular relation to the aforesaid arms, and lost motion connections between the shafts and arms which permit the shafts to rotate independently Aof the arms when the doors are swung above said horizontal position, said connections being such that the shafts and arms move in unison when the doors are swung below horizontal position.

11. In a top loading and unloading oven, in combination with the oven structure, two shafts arranged adjacent the top plane of said structure in substantially parallel relation to each other, said shafts being disposed longitudinally of the oven structure and spaced apart laterally thereof a substantial distance, vdoors carried by the shafts and extending therefrom toward each other in a substantially horizontal plane when the shafts are in normal position, bearings adjacent the ends of the oven structure wherein said shafts are supported for oscillation, an arm journaled on the end of each shaft beyond one end of the oven structure, each shaft and the corresponding arm having, on the one hand, a key or its equivalent, and, on the other, opposed abutments that are spaced apart in a direction circumferentially of the shaft and wherewith said key is adapted to alternately engage, the proportion of the key to the spacing of said abutments being such that the shaft is capable of independent angular movement with respect to the arm of nearly 90, and means biasing each arm to a position in which, by the engagement of the key with one of said abutments, the corresponding-shaft is retained in the position it occupies when the door that is carried thereby is substantially horizontal.

12. In a top loading and unloading oven, in combination with the oven structure, .two shafts arranged adjacent the top plane of said structure in substantially parallel relation to each other, the shafts being disposed longitudinally of the oven structure and spaced apart laterally thereof a substantial distance, doors carried by the shafts and extendling therefrom toward each other in a substantially horizontal plane when the shafts are in normal position, bearings adjacent the ends of the oven structure wherein said shafts are supported for oscillation, an arm journaled on the end of each shaft beyond one end of the oven structure, each shaft and the corresponding arm having, on the one hand, a key or its equivalent, and, on the other, opposed abutments that are spaced apart in a direction circumferentially of the shaft and wherewith said key is adapted to alternately engage, the relation of the key to the spacing of said abutments being such that the shaft is capable of independent angular movement with respect to the arm of nearly a stop wherewith each arm contacts when, through the engagement of said key with one of said abutments, it retains-the corresponding shaft in the position the latter occupies when the door that is carried thereby is substantially horizontal, the arm swinging away from said stop when the door is depressed and the shaft rotating independently of the arm when the door is raised, and counterbalancing means operatively connected to each arm and tending to urge the same into engagement with the corresponding stop.

13. In a top loading and unloading oven? in combination with the oven structure. two shafts arranged adjacent lthe top plane of said structure and in substantially parallel relation to each other, said shafts being disposed longitudinally of the oven structure and spaced apart laterally thereof a substantial distance, bearings wherein said shafts are supported for oscillation, an arm journaled on each shaft, the same having a notch whose end walls are spaced apart circumferentially of the shaft, a key on each shaft occupying the notch in the corresponding arm, stop means wherewith each arm is adapted to engage when in a substantially vertical position, counterbalancing means operatively connected to each arm and tending to urge it into engagement with the stop means and doors connected to and extending laterally from the opposed shafts, the parts being so proportioned and related that the doors are sustained in substantially horizontal position wherein they project toward each other when the arms are in engagement with the aforesaid stop means.

14. In a top loading and unloading oven, ln combination with the oven structure, two shafts arranged adjacent the top plane of said structure and in substantially parallel relation to each other, said 4shafts being disposed longitudinally of the oven structure and spaced apart laterally thereof a substantial distance, bearings adjacent the ends of the oven structure wherein said shafts are supported for oscillation, an arm associated with each shaft. said arm having a hub that is journaled on the shaft beyond one end of the oven structure, the hub having a notch whose end walls are spaced apart circumferentially of the hub, a key on each shaft occupying the notch in the hub of the corresponding arm, the dimensions of the key and notch in a direction circumferentially of theshaft being such that the shaft is capable of rotary motion with respect to the arm through an angle of somewhat less than 90, stop means associated with each arm adjacent the end of the oyen structure and wherewith said arm is adapted to engage when in a substantially vertical position, counterbalanclng means operatively connected to each arm and tending to urge it into engagement with the corresponding stop means. and doors connected to and extending laterally from the opposed shafts toward each other, the parts being so proportioned and related that the doors are sustained in a substantially horizontal position when the arms are in engagement with the aforesaid stop means.

15. In` a top loading and unloadingoven, in combination with the oven structure, two stationary elements `disposed longitudinally loi the oven structure adjacent the top thereof and spaced apart laterally of the structure a substantial distance, a shaft extending along the inner side of each element adjacent the base thereof, hangers carried by each element wherein the adjacent shaft is supported for oscillation, doors secured to the shafts and extending substantially horizontally toward each other when the shafts lare in normal position, and counterbalancing means operatively connected to the shafts for retaining them in normal position, the connections between the shafts and said counterbalancing means being of such a nature that the shafts may rotate independently of the counter-.balancing means and in unison with the door when the latter are swung above horizontal position.

16. In a top loading and unloading oven, in combination with the oven structure, a cover partially closing the top of the oven structure and consisting of portions extending along each side and across the ends of said structure, two shafts arranged in substantially parallel relation to each other longitudinally of the structure adjacent the inner edges of the side portions of the cover, each shaft having one end extended beyond the end of the oven structure, bearings at' the ends of said structure wherein the shafts are journaled, doors secured to and extending substantially horizontally inwardly from the shafts toward each other when the shafts are in normal position, the free edges of the doors being spaced apart when the doors are in horizontal position, an arm journaled on the extended end of each shaft, the arm and shaft having, on the one hand, a key or its equivalent, and von the other circumferentially spaced abutments between which the key is disposed, the spacing apart of said abutments being such that the shaft is permitted angular movement relative to the arm of nearly 90, a. stop wherewith the arm is adapted to engage when, through the interventionof one of said abutments, the key and the shaft, it serves to hold the corresponding door in substantially horizontal position, the shaft being adapted to swing independently of the arm and in unison with the door when the door is swung above horizontal position, and counterbalancing means connected to the arm and tending to hold .it in engagement with said stop.

17. In a top loading and unloading oven, in combination with the oven structure, a cover consisting of portionsextending along each side and across the ends of said structure so as to partially close-the top thereof, the end portions of the cover being notched at approximately the middle of their inner edges, the structure including seats below said notches for the ends of a work supporting beam, outwardly facing channel bars arranged in substantially parallel relation to each other longitudinally of the oven structure adjacent the inner edges of the side portions of the cover, a shaft extending along the inner side of each channel bar adjacent the base thereof and having one of its ends extended beyond the adjacent end of the oven structure, hangers attached to the inner sides of the channel lbars and wherein the shafts are adapted to oscillate, bearings at the ends of the oven structure wherein the shafts are journaled, doors secured to and extending substantially horizontally inwardly from the shafts toward each other when the shafts are in normal position, the free edges of the doors being spaced apart when the doors are-in horizontal position, an arm journaled on the extended end of each shaft, the arm and shaft having, on the one hand, a key or its equivalent, and on the other circumferentially spaced abutments between which the key is disposed, the spacing apart ofsaid abutments being such that the shaft is permitted angular movement relative to the arm of nearly a yielding stop wherewith the arm is adapted to engage when, through the intervention of one of said abutments, the key and the shaft, it serves to hold the corresponding door in substantially horizontal position, the shaft being adapted'to swing independently of the arm and in unison with the door when the door is swung above horizontal position, and counterbalancing means connected-tothe arm and tending to hold it in engagement with said stop.

18. In a top loading and unloading oven, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other,

said elements being disposedlongitudinally of' the oven and spaced apart laterally thereof a substantial distance, doors carried by said elements and extending therefrom toward each other and capable of swinging above and below a substantially horizontal position, means biasing the elements to the position they occupy when the doors are in substantially horizontal position, the doors when in horizontal position having their free edges spaced a material distance apart, and means for closing the space between said edges when the doors arevin said position.

19. In a top loading and unloading oven, in

combination with load handling means, two elements supported for oscillation and arranged in approximately the plane of the oven top and in substantially parallel relation to each other, said elements being disposed longitudinally of the oven and spaced apart laterally thereof a substantial distance, doors carried bysaid elements and extending therefrom toward each other and capable of swinging above and below a substantially horizontal position in response ,to the movements of a load when lifted from or lowered into the oven by said load handling means, counterbalancing means tending to retain the elements in the position they occupy when the doors are in substantially horizontal position, the doors when in horizontal position having their free edges spaced a material distance apart, and a bonnet carried by the load handling means for closing the space between said edges when the doors are in said position.

CARL F. MAYER. 

